Index device



FIG. 2

Nov. 28,1939. T. JENSEN I 2,181,432

INDEX DEVICE Filed June 23, 1938 INVENTOR THORMOD JENSEN BY ATTORNEY 1'53 found that hot loaves Patented Nov. 28, 1939 PATENT orrlcs 2,181,432 INDEX DEVICE 'lhormod Jensen,

Laurelton, N. Y., assignor to American Machine. and Foundry Company, a corporation of New Jersey Application June 23, 1938, Serial No. 215,493

16 Claims.

This invention relates to an intermittent drive mechanism, and more particularly to a device suitable for driving the infeed conveyor of a bread wrapping machine.

6 In operating the infeed conveyor of a bread wrapping machine, it is desirable to move it at such a rate of speed that the loaves are not damaged in being advanced to a point where the loaves are removed from the conveyor and projected for wrapping into the wrapping. structure elements thereof. Heretofore, Geneva gear driving mechanism has been used. However, since this type of driving device necessarily causes a more or less violent change inspeed, it has been of by the conveyor flights have been compressed endwise during the advancing motion. Also the speed at which the conveyor has been advanced has been strictly limited by the design of. the

go Geneva gear drive itself.

According to the present. invention there has been provided an intermittently operable driving, mechanism wherein the infeed conveyor is moved from loaf receiving to loaf discharging position at a higher and more or less constant rate of speed with the net result that substantially all of the above-mentioned disadvantages have been eliminated.

It is an object of the invention to provide inter 39. mittently operated driving means capable of driving at higher speeds than heretofore obtainable with devices of a similar nature wherein a driving cam is provided, the shape of which cam can be controlled to suit the speed required for the 35 particular need.

It is a further object of the invention to pro-- vide an intermittent driving mechanism wherein a rotating cam coacts with a driven member to effect the intermittent operation of a conveyor and in which means are provided for preventing locking of. the driving and driven members.

It is a further object of the invention to provide an intermittent drive mechanism wherein a driving cam member coacts with a driven ele- 45, ment, and the wear between the cam and the element is reduced to a minimum.

With these and other objects not specifically mentioned in view, the invention consists in certain combinations and constructions which will so be hereinafter fully described, and then specifically set forth in the claims hereunto appended.

In the accompanying drawing which forms a part of this specification, and in which like characters of reference indicate the same or like in; parts:

bread being advanced Fig. 1 is a partial side view of a wrapping machine showing the arrangement of the index device in which a gear is omitted to more clearly illustrate the under parts: and

Fig. 2 is a plan View taken from line 2-2 of 5' Fig. 1, and includes the gear omitted from Fig. 1.

Referring to the drawing, the indexing device which may be of general application for intermittently driving various machine parts, but which in the instant application has been designed primarily for indexing the infeed conveyor of a bread wrapping machine, consists of a driving member or cam it mounted at M upon a cam shaft i2 which is suitably driven by the drive shaft of the bread wrapping machine (not shown). The driving member H3 is provided with a cam track 13 having a circular, and a noncircular portion which extends outwardly with a single high point M close to the periphery of member Ill. Perpendicular to the radius at the high point l4 and at a center distance from that point substantially equal to the distance between the rollers I5 and I6, is a by-pass ll which ex tends across the cam from one side of the track to the other. It will be noted that the by-pass is located between the center of the high point it and the shaft II. The distance of the by-pass from the center of the high point is fixed by the spacing of the rollers of the driven member 18.

The driving member in, which is normally go maintained in continuous rotation by means of shaft I2 upon which it is mounted, cooperates with and drives member is. According to the invention, and as illustrated in Figs. 1 and 2, driving member l8 assumes the general form of a disk, and has located thereon at fixed points 180 apart, cam followers l5 and 16,-which engage with and travel in cam track it of the driving member In. Due to the engagement of the cam followers 15 and It with the cam track is, 40 and more particularly with the non-circular portion thereof, the indexing of the shaft it upon which driven member 18 is mounted, is effected.

Mounted adjacent the high point it of the driving member Ill and located on either side thereof at an appropriate angle, with a line passed through the center of the high point and the shaft l2, are rollers 20 which engage with the cam faces formed on member 18. While the position of the rollers 2li' -may be varied either to or from the line above referred to, experimentation has shown that an angle varying between 0 and 30 gives very satisfactory results. This angle is determined by the curve of the desired cam track and the pressure angle. Inthe illustrated embodiment, however, this angle is approximately 20. This arrangement makes it possible to drive shaft i0 intermittently at higher speeds obtainable with devices heretofore known which approach this general type of mechanism where there has been excessive wear on the several parts thereof, or there has been a tendency for the co-acting member thereof to lock and jam at the highest point of the non-circular cam track due to the excessive pressure angle, especially at the high point, and more particularly has this been true when the speeds were raised to an appreciable number of revolutions per minute.

According to the invention, the rotation of driving member ID and the coaction of track M with followers l5 and iii with driven member l8, causes the shaft is to be intermittently rotated. If either rollers IE or iii, as the case may be, approach the zone of the high spot of. the noncircular portion of cam track l3, where there is a tendency to lock, positive means in the form of rollers 20 on driving member and cam faces on driven member 18 come into engagement approximately 20 before the high spot has been reached. At this moment the drive which has heretofore been effected by the coaction of followers 15 and I5 and cam track it, is transferred therefrom and taken up by the engagement of rollers 20 with the cam faces on the driven member I8. This engagement continues until the high spot has been reached and passed, and at a point approximately 20 beyond the high spot, the drive is returned to followers i5, it and cam track it. It will be apparent, therefore, that this arrangement allows the cooperation of the rollers 20 on the driving cam and the periphery 2! of the driven member, and insures that the cam followers on the driven member are always successfully and positively moved past the highest point or high point it of the non-circular cam driven portions. Hence satisfactory operation of the driving mechanism can be accomplished both at high speed and without danger of locking be-. tween the cam track l3 and the followers l5 and I 6 tracking therein.

One complete rotation of the driving member III, which takes place once during each cycle of the machine, causes a 180 rotation of driven shaft I 9. From this it follows that whenever cam follower I5, as shown in Fig. 1, is moving past the high spot I 4 in the direction of the arrow, follower I0 is moving along the by-pass Hi At the high spot, as described above, roller l5 has lost its driving force due to the engagement of roller 20 with the leading cam face 21 on disk l8. Continued movement of the disk It causes follower 6 to move out of the by-pass and be swung around into a position to be operative for causing the next 180 indexing of the shaft 19 on the cycle of the machine. Under some conditions, such as for ease in manufacture, it may be desirable to recess the by-pass somewhat as shown in Fig. 1.

At the completion of the engagement ofthe high portion of the cam track with either of the cam followers 55 or [6, the shaft l9, and attached member, have been rotated one-half of a revolution'or 180, as mentioned above, and the turning of shaft 19 will then be prevented because both of the cam followers l5 and E6 are engaging in the circular portionof the cam track 13 and no driving movement can be imparted to shaft l9 until either follower l5 or 16 enters the non-circular portion of the track l3. If it be desired to index a shaft through angles less than 180, such as or 60, additional cam followers can be fixed to disk I8.

As shown in Figs. 1 and 2, the intermittent rotation of shaft I 9 through beveled gears 22 and 23, imparts step by step movement to conveyor flights 2'1, which form part of a conveyor running over a double sprocket 26. In this manner, loaves or packages P are intermittently propelled over a runway platform 28 of the wrapping machine which leads to the wrapper applying position.

The invention above described may be varied in construction within the scope of the claims for the particular device, selected to illustrate the invention, is but one of many possible concrete embodiments of the same. The invention is not, therefore, to be restricted to the precise details of the structure shown and described.

What is claimed is: v

l. A driving mechanism for intermittently driving a conveyor comprising, a rotating shaft, a driving member fixed to said shaft, spaced driving surfaces formed on said member, driven connections between said driving member and conveyor including, a driven member, devices engaging said driving member mounted on said driven member, each of said devices being arranged to engage first one and then the other of said surfaces to index said conveyor, and auxiliary means carried by said driving member for transferring the drive from one of said surfaces to the other during each cycle of the machine.

2. An index mechanism for intermittently driving a conveyor comprising, a rotating shaft, a driving cam mounted on said shaft and provided with a cam track on one of its faces, a driven shaft, and a driven member fixed thereto, driving connections cooperating with said driven shaft for transferring the intermittent drive to said conveyor, cam followers mounted onone face of said driven member and located diametrically opposite one another, said followers being arranged to engage said track in said cam for driving the cam member during a part of the revolution, and rollers mounted on said cam for engaging said driven member to transfer the drive from said cam followers to said rollers'once during each revolution of the cam.

3. In a driving mechanism, a rotating shaft, and a driving member fixed to said shaft, spaced driving surfaces formed on said member, a driven shaft and a driven member mounted thereon, devices engaging said driving member mounted arranged to engage first one and then the other of said surfaces to index said driven shaft, and auxiliary means carried by said driving member for transferring the drive from one of said surfaces to the other during each cycle of the mechamsm.

4. In an indexing mechanism, a rotating shaft, a driving cam mounted on said shaft and provided with a cam track, a driven shaft, and a driven member fixed thereto, cam followers mounted on one face of said driven member and located diametrically opposite one another, said followers being arranged to engage said track in said cam for driving said driven member during part of the revolution of said cam, and rollers mounted on said cam and member to transfer the drive from said cam followers to said rollers once during each revolution of the cam.

5. In a driving mechanism, a continuouslyroengaging said driven tating shaft, and a driving cam fixed to said shaft, said cam being provided on one of its faces'with a continuous track having a circular and a non-circular portion provided with a high part; a driven shaft, and a driven member mounted thereon, devices mounted on saiddriven member and-running in said track, each of said devices being arranged to engage first one and then the other of the cam portions adjacent the high part of said track to index said driven shaft, and auxiliary means carried by said driving member for transferring the drive from one of said surfaces to the other during each complete revolution of said cam. V

6. In a driving member, a continuously rotating shaft, a driving cam fixed to said shaft, a circular cam track formed in said cam and provided with a non-circular section having a high part, and a circular portion; a driven shaft, a driven member mounted thereon, a plurality of driving devices located on a face of said driven member, and at diametrically opposite points thereon, one of said devices being arranged to engage first one and then another portion of said non-circular section to index said driven shaft, and auxiliary means located adjacent the periphery, and on one face of said cam for engaging said driven member to transfer the drive from one of said portions of said section to the other during each revolution of said cam.

'7. The combination with a driving shaft provided with a driving member, of a cam track formed in said member and provided with a noncircular section having a high part, a by-pass connecting the opposite portions of the non-circular section of said track; a driven shaft, a disk mounted on said shaft, a plurality of cam followers mounted on one face of said disk at diametrically opposite points thereof and running in said cam track, cam rollers mounted on said driving member adjacent the periphery thereof and on either side of said high part, cam faces formed on the said disk, said cam faces being adapted to engage said rollers whereby the continued rotation of said member transfers the drive from said followers to said rollers during an intermediate portion of each revolution of said member.

8. In an indexing mechanism, a continuously rotating shaft, a driving cam mounted on said shaft, a cam track formed in one face of said cam, provided with a circular portion and a noncircular section having a high portion extending toward the periphery; a driven shaft, a disk mounted on said shaft, said disk being provided with a plurality of driving devices located on one face and at diametrically opposite points thereof, one of said devices being arranged to track in said section during each revolution of said cam, and means mounted on said cam on a line passing through the peak of said high part,

and driving shaft for insuring the positive and uninterrupted movement of said driven shaft during themovement of said device along said non-circular section.

9. The combination with a driving shaft provided with a driving member, of a cam track formed in said member and provided with a noncircular high .portion, a by-pass connecting the a disk mounted on said shaft, a plurality of cam followers mounted on'one face of said disk at diametrically opposite points thereon and running in said track, cam faces formed on the periphery of said disk and extending on each side of each of said faces, rollers mounted on portion, a drivenshaft and adjacent the periphery of said driving member and on lines extending at an angle varying between 0 and 40 with a radius passing through the center of the drive shaft and the center of the high part of said track, said rollers being arranged to coact with the cam faces of said disk for transferring the index imparting force of said driving shaft from one part of the non-circular portion of the cam track to another.

10. In an "indexing mechanism, uously rotating shaft, a driven member fixed to said shaft, a circular cam track formed in one of said cam faces and provided with a noncircular section having a high portion extending towards the periphery thereof, a driven shaft, a disk mounted thereon, a plurality of driving devices located on one face of said disk and at diametrically opposite points, cam surfaces formed on the periphery of said disk and on each side of said devices, said devices being so constructed and arranged that one device tracks in said section during each revolution of said cam, and means carried by said cam and coacting with the cam surfaces on said disk for transferring the drive from one part of said section to another during each half-turn of said disk.

11. The combination with a driven shaft, of a disk mounted on said shaft and provided with two followers located on a face thereof at diametrically opposite points, a continuously rotating shaft, a rotatable driving member mounted on said shaft, a circular cam track formed on said member and arranged to receive both of said followers to lock said driven shaft against rotation, said track also non-circular portion, a by-pass connecting the opposite portions of said non-circular track adapted to receive one of said rollers while the other is engaged by the non-circular portion of said track, said continuously rotating shaft being operative to successfully cause each of said rollers to enter the non-circular portion of said shaft and rotate said and rollers mounted on said member adjacent the high portion of said cam track and on either side thereof for transferring the drive from said followers to drive said disk once during each revolution of said driven member.

12. In an indexing device, a driving member mounted upon a continuously rotating shaft, said driving member being provided with a cam track having a circular, and a non-circular portion provided with a high spot adjacent the periphcry of said member, a by-pass lying between said high spot and said shaft connecting opposite portions of said track, a driven shaft, a driven member mounted on said shaft, a plurality of cam followers mounted on said driven member at diametrically opposite points thereof, one of said followers being adapted to travel in the non-circular portion of said track while the other is passing through the by-pass, and means mounted on said driving member and engaging said driven member for transferring the drive from said cam followers to said rollers once during each revolution of said driving member.

13. In an indexing device, a continuously rotating driving shaft, a driving member located on said shaft and provided with a cam track having a non-circular portion, and a by-pass, drivingrollers located on said member adjacent the high portion of said cam a continshaft one-half turn,

being provided with a track and 76 equally spaced on opposite sides thereof, a driven member provided with a plurality of cam followers located' diametrically opposite one another on said disk and engaging said cam track, one of said followers being adapted to travel through said by-pass during the movement of the other follower through the non-circular portion of said cam track to drive said driven shaft, and cam faces provided on said disk adjacent each of said followers for transferring the drive from said cam followers to said rollers once during each revolution of said driving member.

14. In a driving mechanism, a continuously rotating shaft, a driving cam fixed to said shaft, a continuous cam track formed on one face of said cam, and provided with a non-circular section having a high part, and a circular portion, the peak of said high portion being approximately 90 from a line passing through said shaft and the line joining said shaft and said peak, a driven shaft, a disk mounted on said driven shaft, a plurality of cam followers mounted on one face of said disk and running in said track, one of said followers being arranged to travel in said section during each revolution of said cam to index said disk one-half turn, said circular portion being so positioned with respect to said non-circular portion that rotary movement of said driven shaft is terminated as soon as the followers running in the non-circular section enter the circular portion of said track.

15. The combination with a driven shaft, of a disk on said shaft provided with two rollers mounted on one of its faces at diametrically opposite points thereof, and cam faces adjacent each of said rollers, a rotatable cam provided with a circular cam track receiving both of said rollers to lock the shaft against rotation, said track being provided with a non-circular portion and a by-pass connecting the opposite parts of said non-circular portion of said track and. being adapted to receive one of said rollers while the other is engaged by the non-circular portion of the track, a drive shaft arranged to rotate said cam continuously to cause each of said rollers successively to enter the non-circular portion of said track and rotate said shaft one-half turn, and spaced rollers mounted on said driving member for engaging said faces formed on the disk for driving said disk during a portion of each half-turn movement of said driven shaft.

16. The combination with a driving shaft, provided with a driving member, of cam surfaces formed on said member and provided with a non-circular high portion, cam rollers mounted on said driving member adjacent the high part of said non-circular the limits of 0 and 30 on either side of a line passed through the center of said high part and the driving shaft, a lay-pass formed by said cam faces and located between said high part and the driving shaft, a driven shaft, a disk mounted on said shaft, a plurality of cam followers mounted on one face of said disk at diametrically opposite points thereof, and engaging said cam surfaces, one of said cam followers being arranged to engage the non-circular portion of the said cam surfaces while the other is travelling along the said by-pass, and means on said disk adapted to engage said driving rollers to transfer the drive of said disk from said cam surfaces and cam followers whenever a cam follower approaches the high part of said cam surfaces.

THORMOD JENSEN.

portion and situated within 

